Steam-boiler



JOI-IN T. FANNING, OF MINNEAPOLIS, MINNESOTA.

STEAM-BOILER.

SPECIFICATION formingpart of Letters Patent No. 552,318, datedlllgcember 31 1895.

'Application filed June 29, 1895. Serial No. 554,449. (No model.) T

To all whom t may concern/.-

Be it known that I, JOHN T. FANNING, engineer, residing at Minneapolis,Hennepin county, in the State of Minnesota, have-invented a certain newand useful Improvement in Steain-l3oilers, of which the following is aspecification. v A

The boiler is of that class which presents a shell, or preferably twoshells, mounted side by side and traversed by tubes, with the grate ofany suitable form and style, at a proper distance below, and withliberal con-Y nections from these shells upward into a combinedgenerating and separating` drum in which steam generated is disengagedfrom the water, and the water is returned downward to the shells bysimilar liberal connections so arranged as to induce and maintain alongitudinal circulation in a circuit through the drum and shells. Theweight of this form of boiler and its contents is very great. Myinvention is intended to avoid the difliculties ordinarily met insupporting it and allowing for expansion and contraction with heat andcold. I hold the front ends of the tubular shells in a fixed positionand allow the rear ends to move backward and forward, as has long beenpracticed. The weight is sustained at the back partly by rollersunderneath and partly by slings which suspend the weight from pointsoverhead. The slings are equipped with springs which, while maintaininga nearly uniform strain on the slings and girders, allow by theirelasticity for imperfections in the workmanship and adjustment and forsettling or changes which may occur, and for vertical expansion andcontrac- I tion of the parts by changes of temperature.

I endeavor to so adjust the slings that they will support aboutthree-fourths of the weight, leaving the other quarter to run on therollers.

The invention gives assurance of the exact position of the boiler underall conditions, while relieving the rollers from excessive loads.

The accompanying drawings form a part of this specication and representwhat I consider the best means of carrying out the invention.

Figure l is a vertical cross-section on the line l l in Fig. 2. Fig. 2is a side elevation with a side wall removed, and Fig. 3 is a horizontalsection of a portion on a larger scale. The illustrations show aywater-grate used therewith.

Similar letters of reference indicate corresponding parts in all thefigures where they appear.

A is the boiler front, constructed with supporting-lugs Kin any ordinaryor suitable manner.

B B are inclined shells traversed by tubes h. Connections O O2 O3 uniteeach of these shells with a horizontal separating-drum D above. Theshells B, with their connections O', dto., and the separating-drum D,constitute the main body of the boiler. The weight of a part of the backend is carried on a shoe, bolted on the under face of each shell B atthe rear end, as shown by B. Rollers E are interposed and inc'losedbetween each shoe B and a stationary way A', supported on a foundationbeneath. The free turning of the rollers allows the rear end of theboiler to move forward and backward to accommodate the expansion andcontraction.

. F F are stout girders placed by the sides of the separating-drum D andbelow the top thereof, and adapted to support any required portion ofthe weight of the structure, while not extending to any greater heightthan the top of the separating-drum.

G G are slings secured by straps G to the shells B B, two or more pairsof slings for each shell. The slings converge and extend upward throughclamps I. The lower portion of each sling Gis flat and thin and standsinclined, but the upper end of each is formed into a screw-threaded boltextending upward through the interior of the clamp I andv through across-plate J and a helical spring H and receives a nut G2. Each slingsupports a portion of the weight of the boiler, and its strain istransmitted through the springs I-I II to the corresponding girder F.The nuts allow of adjustment of tension of the respective slings, sothat any required portion of the strain due to the weight of the boilermay be transmitted through the several springs lvI to the girders F,while the remainder of the weight is carried on the lugs K, shoes B androllers E below. When the temperature is high the boiler increases inlength and the rollers E allow the boiler to elongate rearward, and whenthe temperature lowers the parts return to their original positions. Inthis movement the slings G swing forward and backward to the extentrequired, exerting a nearly-constant lifting force acting through thesprings II. The nuts G2 should be adjusted to sustain a liberal portionof the weight, and relieve the rollers E from excessive load Whileallowing them to serve in maintaining the proper level of the rear endof the boiler.

It will be seen that besides providing for the expansion and contractionoi' the boiler longitudinally, the expansion and contraction of theboiler vertically are allowed for by the action of the springs II, theseelongating and lifting the nuts G2 when the temperature is high and themetal expands, and being compressed and lowering such nuts when theboiler cools.

The plate J is important in receiving the load and transmitting it tothe girder. The clamps I are important because they hold the slingsproperly inward at the base of the girders so that the upper portions ofthe slings are parallel and the nuts can bear fairly on the plate .Iwhile the lower portions of the slings diverge.

The nuts G2 are adjusted from time to time to allow for permanentchanges, while the springs II allow by their elasticity for temporarychanges which occur in ring up and cooling oit the boiler.

I claim as my inventionM l. In a steam boiler support, the longitudinalgirders F, arranged along the sides of and not higher than theseparating drum D and out oi' contact therewith7 slings G connectingfrom such girders to inclinedshells B below, the clamps I holding theupper portion of the slings inward, and the cross plates J above thegirders for receiving the load, in combination with means G2 foradjusting the slings, all arranged to serve substantially as hereinspecified.

2. In a steam boiler support, the longitudinal girders F, arranged alongthe sides oi' and not higher than the separating drum I), out oi'contact therewith, slings G connecting from such girders to a shell B ata lower level, the clamps I holding the slings inward, the cross platesJ above the girders, and springs ll encircling the slings and adapted toexert a yielding tension, combined as herein specified.

3. In a steam boiler, the inclined shell or shells B, connections C' C3and generating and separating drum D, having lugs K, ways A', shoes Band rollers E, arranged to support in part the weight of the drum,shells and con tents,in combination with the slings (T,springs Il andnuts G2, adapted to transfer with practcally uniform strain the remaining portion of the weight to fixed supports above and to allow by theswinging oi the slings and by the elastic action of the springs for bothhorizow tal and vertical changes in the dimensions o[i` the boiler withchanges of its temperature, all arranged for joint operationsubstantially as herein specified.

In testimony that I claim the invention above set forth I ailix mysignature in proscnce oi' two witnesses.

JOHN T. FANNING. lVitnesses CLARENCE V. KENDALL, M. F. BoYLE.

